Tension equalizing apparatus



y 9 1950 Y. A. BOUGET 2,507,297

TENSION EQUALIZING APPARATUS Filed Nov. 26, 1948 2 Sheets-Sheet 1INVENTOR m. BOUGEZ" BY A T TOPNEV May 9, 1950 Y. A. BOUGET TENSIONEQUALIZING APPARATUS [[HIH IIv Filed Nov. 26, 1948 INVENTOR KABOUGET Afrom/5v I Patented May 9, 1950 TENSION EQUALIZING APPARATUS Yves A.Bouget, West Orange, N. J., assignor to Western Electric Company,Incorporated, New York, N. Y., a corporation of New York ApplicationNovember 26, 1948, Serial No. 62,153

This invention relates to apparatus for equalizing tension in materialpulled from a rotatable supply of the material and has for its object asensitive mechanism affected by variations in the pull on the materialat the supply to create.

constant tension in the material.

The speeds at which material handling machines may operate dependlargely upon the eiliciency of the mechanisms associated therewith incontrolling the tensions in the materials. During unwinding of sheetmaterial from a supply roll, by pulling the material from the supply,there will exist the problem of the gradually diminishing diameter ofthe supply roll effectin a gradual increase in tension. During unwindingof strand materials from reels the effective variations in the supplieson the reels occur only at the end of one layer of convolutions and thebeginning of another layer. This factor is more disturbing than thegradual increasing of tension in the sheet material in that there is atendency for the strand material to be shocked by these sudden changesresulting in possible damage to the strand material if a highlysensitive mechanism is not provided to allow for these abrupt attemptsto vary the tension in the material.

With the aforementioned object in view, the invention comprises anapparatus for equalizing the tension in material pulled from a rotatablesupply of the material, the rotation of the supply resulting from thepull on the material being removed from the supply. The apparatus isemployed in combination with a variable displacement fluid pistonmotor-pump having a shaft rotatable about a fixed position axis and.

a compensator variable with variations of tensions in the material toact as a controlling factor. The tension equalizing apparatus includes acradle supported for rocking movement about the axis of the shaft and isformed to receive a spindle for removably supporting the supply ofmaterial. The material supply is caused to rotate with the spindle and aunit is variable, depending on the tension to be created in the materialpulled oif the supply, to normally urge the cradle in a directionopposite the direction of pull of the material on the supply. Amechanism operatively connecting the spindle and the shaft causesvariation of the pressure of. the

fluid in the control motor-pump unit with variations of the tension inthe material, and as a result of the motor-pump unit will act as eithera. motor or a pump to correct such irregularities in tension.

6 Claims. (cl. 242-45) More specifically, the cradle is substantiallyU-shaped in general contour, the upper ends of the vertical portionsbeing formed to removably receive the spindle, whereby the reel orsupply of material may be readily loaded in the cradle and urged intoits starting position by the pulling force of the variable tensionsetting unit. The tension setting unit contains a helical springconnected at one end to the cradle, whereby a predetermined forcecomparable to the tension to be created in thevmaterial is applied tothe carriage in a direction opposite the pull of the material from thesupply.

Other objects and advantages will be apparent from the followingdetailed description when considered in conjunction with theaccompanying drawings, wherein Fig. 1 is a front elevational view of theapparatus;

Fig. 2 is a side elevational view of the apparatus, portions thereofbeing removed; and

Fig. 3 is a fragmentary sectional view taken along the line 3--3 of Fig.1.

Referring now to the drawings, the apparatus includes a cradle l0 whichis U-shaped in general contour, one leg 9 of the cradle carrying a stubshaft II, ijournalled in a'bearing I2,

mounted upon a vertical member I4. The other leg I5 01 the cradlesupports a housing I6 through which a shaft I'I extends in axialalignment with the shaft II. The outer end of the shaft I1 is journalledin a fixed position bearing I8 mounted u on a vertical member I9 whilethe inner end of the shaft is journalled in the leg I5.

The shaft I! has a pinion 20 mounted thereon and interengaging a gear 2|of a shaft 22. The pinion 20 and the gear 2| are disposed in a housing I6, the open end of the housing being closed by a cover 24 which isprovided with suitable bearing portions for the outer ends of the shaft22 and also a shaft 25. The inner ends 01'- the shafts 22 and 25 arejournalled in the leg I5 of the cradle Ill. The shaft 22 has a sprocket26 mounted thereon which is operatively connected to the shaft 25through a chain 21 and a sprocket 28, the latter being mounted on theshaft 25. A handle 29 formed integral with the housing I6 projectsoutwardly therefrom, as illustrated in Fig. 2 and is provided with anindicating point 30 at the outer end thereof.

The shaft 25 extends inwardy through the housing I 6 and has an enlargedportion 3| disposed in the notched upper end 32 of the leg portion I5 ofthe cradle III and has a recess 38 therein. A spindle 34 is positionedin the hub of a reel 35 of strand material 2', the spindle having aconical portion 28 to cause centering of the spindle in the reel. Thespindle is also provided with a pin supporting flange 39 for engagementwith the reel. The innermost portion 40 of the spindle is receivable inthe recess 33 of the shaft 25 (Fig. 3) when the reel with the spindle ispositioned in the cradle ID. The other end of the spindle 24 has athreaded portion 4| upon which a nut 42 is mounted removably securingthe spindle within the reel. The extreme outer end 43 of the spindle isremovably journalled in a bearing 44 disposed in a notched outer end 45of the adjacent leg 9 of the cra le It.

A hood-like casing 48 mounted on a suitable support 49 partially housesthe reel when loaded in the apparatus, the sides II and Si of the casingbeing cut away at 52 to allow movement of the cradle with the reel fromthe loading position shown in broken lines in Fig. 2 to the startingposition shown in solid lines in this figure. A latch 53 pivotallysupported at 54 on theside of the casing 42 is normally disposed in theposition shown in Fig. 2 with its lip portion 55 disposed in the path ofthe side 9 of the cradle In to hold the cradle with the reel againstmovement into its loading position. A handle 56 of the latch projectsoutwardly whereby the operator may readily actuat the latch when it isdesirable to unload the empty reel. Arcuate portions 51 of the cut awayportions I2 serve to hold the ends of the spindle in the notched ends 22and 45 of the cradle Ill.

A tension setting unit 6| is mounted on the side 50 of the casing42,.this unit including a dial 8| graduated to represent variable forcestov be applied to the cradle through a cable 62 connected to the handle29 by 'a couplin 62. The cable 62 is connected to an inner structure ofthe unit 60 which includes a helical spring (not shown), the force ofwhich may be varied by moving the dial 6| relative to a pointer 24. Thepull on the handle 29 tending to rotate the cradle with the reelcounterclockwise into the position shown in solid lines in Fig. 2 willassist in determining the tension to be maintained in the strandmaterial 36 as it is pulled oi! the reel 35.

The apparatus thus far described is used in combination with a unit 66commercially known as a variable displacement piston pump-motorcontrolled by a pressure actuated compensator as shown in detail inPatent 2,351,264 to F. T. Har-, rington et al. of June 23, 1944. Theunit 6" is adapted-to operate either as a pump or motor depending uponconditions within the fluid line 6! affected by the connection of theunit to the shaft I1 through its output shaft 48 and coupling 69.

Considering now the operation of the apparatus, it will be understoodthat a full reel 25 of strand material 36 may be readily loaded into theapparatus by first mounting the spindle 24 in the reel and locating thecradle In in the broken line position shown in Fig. 2. The 'reel 3| maybe rolled on the support or floor 48'until the spindle is received inthe cradle and is properly connected to the shaft 25 through the memvaryin these characteristics depending upon the number of insulatedelectrical conductors assembled in the cable. It is therefore arrangedthat the tension to be created in the material will be such that duringnormal operation of the apparatus for medium or heavy reels, the pointeron the handle 29 will register with a point 10 on the side of thecasing, this being the vertical position of the cradle.

The unit 66, that is, the pressure-actuated compensator 12 thereof isadjusted before the strand material is pulled off the reel. Therefore,when the pulling operation starts, the reel will be moved with thecradle against the force embodied in the unit until the cradle is-in itsoperating position with the marks II and III registering. If thediameter of the reel or the lever arm at .the point of take of! of thematerial from the reel remained unchanged, the'unit 82 perhaps couldfunction in maintaining the predetermined tension in the material.However, the lever arm or the effective diameter of the reel diminishesas each layer of material, is removed therefrom, tending to increase thetension in the material. During rotation of the reel, in a clockwisedirection (Fig. 2) the shaft 25 is rotated in the same direction causingits sprocket to move the chain 2lto rotate the shaft 22 in the samedirection. The shaft 22 will drive its gear 2| to drive the pinion 20with the shaft I! in a counterclockwise direction, this driving forcecontinuing through the coupling 88 and the shaft 68 into the unit 66. Byprearranged setting of the pressure actuated compensator 12 of the unit'8, it is intended that a predetermined pressure be maintained in theunit. An increase of tension in the material will be translated throughthe reel and the connecting mechanism to the unit-6i, causing anincrease in the pressure in the unit. The compensator 12 will beaffected by this increase in pressure in the unit 68 and will convertthe unit from a pump to a motor,

V driving the connecting mechanism leading to the bers 3| and 40. By theaid of the handle 29 thecradle with the reel may be moved about the-axesof the shafts I! and 68 into the position shown in solid lines in Fig.2. The tension to be established in the strand material 36 dependslargely upon the size, weight and strength of the material. In thepresent embodiment of the invention, the material 86 is electrical cablewhich may reel until the predetermined tension has again beenestablished in the material and the predetermined pressure in the unit86 has again been established. If for any reason the tension in thematerial should be reduced, the connecting mechanism between the reeland the unit 66 would affect reduction in the pressure in the unit 66.The'compensator lliwould then cause the unit to speed up its pumpingaction until the pressure therein has reached the prearranged pressureaffecting a drag on the .shaft H, which would be translated through theconnecting mechanism to the reel until the slack in the material hasbeen removed and the prearranged tension established.

The tension equalizing apparatus employed in combination with the unit86 provides for the automatic reduction of the pumpto the constantvolume requirement of the power pump at a maintained predeterminedressure. Therefore,

during the. operation of the apparatus, as the I payoff reeldecreases'in diameter, it will increase in speed as a result of theconstant linear velocity of' the material. The constant volumerequirement of the unit 66 will immediately create a pressure risetendency as aresult of the increased speed of the 'unit. This pressurerise tendency will immediately cause tension control response tovary thecompensator 12 of the unit 66 in the direction of decreasing angulardisplacement with lncreasing speed for a constant volume output atmaintained'pressure,

A sudden slackening'of the cable tension permits the reel cradle toswing backward under the pull of the unit 60. This action causes theepicyclic gearing arrangement to speed up the pump temporarilyincreasing its braking action and slowing down the reel. A suddentightening of the cable temporarily speeds up the reel. The slightestchange in the cable tension instantly starts corrective measures torestore the initial set tension. An arcual displacement of the cradleand reel from the operating position cushions the sudden change in thecable tension. Furthermore, an instantaneous but temporary speed-up orslow-down of the unit 66 takes place to decelerate or accelerate thereel rotation.

To achieve a more sensitive control of light tensions of smaller cablesor strands on lighter and smaller reels, it will be advantageous to havethe operating position of the cradle l forward of the dead centerposition with registration of the points 30 and for the medium or heavyreels. As a result, the force of gravity exerted on the reel and cradlewhen moving in the general direction of the cable pull will assist inprovidin a softer cushioning effect against overtension in the cable. Inaddition to this, the accelerating force of gravity will compensate forthe tension increase which occurs in the hold back spring of'the unit 60for the reel cradle. The slower action of the reel cradle retarded bygravity, in its backward travel to take up cable slack prevents overcorrection when attempting to take up excessive slack. This will preventsudden and wide swaying of the tension control medium and will thereforeindirectly prevent excessive tension in the cable. The gradualdecreasing weight of the light reel, due to the paying off of the lightcable will permit a rightening of the reel cradle and cause it to assumeoperating posit ons closer to its vertical or dead center position. Thiswill tend to retain the same reel torque condition from the start to thefinish of cable unwinding from the reel.

It is to be understood that the above described arrangements are simplyillustrative of the application of the principles of the invention.Numerous other arrangements may be readily devised by those skilled inthe art, which will embody the principles of the invention and fallwithin the spirit and scope thereof.

What is claimed is:

1. An apparatus for equalizing the tensions in materials pulled fromrotatable supplies of materials, in combination with a variabledisplacement fluid piston motor-pump unit having a shaft rotatable abouta fixed position axis and a compensator variable with variations oftensions to be created in the materials to maintain a selected variablepressure of the fluid in the motor-pump unit comparable to the tensionsto be created in the materials, the apparatus comprising a cradlesupported for rocking movement about the axis of the shaft into and outof an operating position, a spindle for supporting a supply of material,mounted for rotation on the cradle, means to connect the supply ofmaterial to the spindle whereby the spindle will be rotated with thesupply when the material is pulled therefrom, means variable, dependingon the tension to be created in the material pulled oif the supply, tonormally urge the cradle with the supply in a direction opposite thedirection of the pull of the material from the supply, and meansoperatively connecting the spindle and the shaft whereby movement of thecradle out of its operating position, as a result of variation of thetension in the material from a predetermined tension, will causevariation in the pressure of the fluid in the unit rendering thecompensator effective to cause the unit to affect the rotation of thesupply to change the tension in the material to the said predeterminedtension.

2. An apparatus for equalizing the tensions in materials pulled fromrotatable supplies of materials, in combination with a variabledisplacement fluid piston motor-pump unit having a shaft rotatable abouta fixed position axis and a compensator variable with variations oftensions to be created in the materials to maintain a selected variablepressure of the fluid in the motor-pump unit comparable to the tensionsto be created inthe materials, the apparatus comprising a cradlesupported for rocking movement about the axis of the shaft into and outof an operating position, a spindle for supporting a supply of material,mounted for rotation on the cradle, means to connect the supply ofmaterial to the spindle whereby the spindle will be rotated with thesupply when the material is pulled therefrom, means variable, dependingon the tension to be created in the material pulled off the supply, tonormally urge the cradle with the supply in a, direction opposite thedirection of the pull of the material from the supply, and a mechanismoperatively connecting the spindle and the shaft whereby movement of thecradle in one direction out of the operating position by an increase ofthe tension in the material will cause the unit to function as a motorto drive the shaft, the mechanism and the spindle with the supply untilthe tension in the material is reduced to the predetermined tension.

3. An apparatus for equalizing the tensions in materials pulled fromrotatable supplies of materials, in combination with a variabledisplacement fluid piston motor-pump unit having a shaft rotatable abouta fixed position axis and a compensator variable with variations oftensions to be created in the materials to maintain a selected variablepressure of the fluid in the motor-pump unit comparable to the tensionsto be created in the materials, the apparatus comprising a cradlesupported for rocking movement about the axis of the shaft into and outof an operating position, a spindle for supporting a supply of material,mounted for rotation on the cradle, means to connect the supply ofmaterial to the spindle whereby the spindle will be rotated with thesupply when the material is pulled therefrom, means variable, dependingon the tension to be created in the material pulled off the supply, tonormally urge the cradle with the supply in a direction opposite thedirection of the pull of the material from the supply, and a mechanismoperatively connecting the spindle and the shaft whereby movement of thecradle in one direction from the operating position by the said pullingmeans as a result of a decrease in tension in the material will causethe unit to function as a pump creating a drag on the shaft, theconnecting mechanism, the spindle and the material until the tension inthe material is returned to the predetermined tension.

4. An apparatus for equalizing the tensions in materials pulled fromrotatable supplies of materials, in combination with a variabledisplacement fluid piston motor-pump unit having a shaft rotatable abouta fixed position axis and a compensator variable withvariations oftensions to 7 be created in the materials to maintain a selectedvariable pressure of the fluid in the motor-Dump unit comparable to thetensions to be created in the materials, the apparatus comprising a U-shaped cradle supported for rocking movement between a loading positionand the operating position'about the axis of the shaft into and out ofan operating position and having spindle supporting recesses in theupperends thereof, a spindle, for supporting a supply of material,removably mounted in the recesses of the cradle, means toconnect thesupply of material to the spindle whereby the spindle will be rotatedwith the supply when the material is pulled therefrom, means variable,depending on the tension to be created'in the material pulled off thesupply, to

normally urge the cradle with the supply in a direction opposite thedirection of the. pull-oi the material from the supply. and meansoperatively connecting the spindle and the shaft whereby movement of thecradle out'of its operating position, as a result of variation of thetension in the material from a predetermined tension,

will, causevariation in the pressure of the fluid 4 in the unitrendering the compensator effective ,to causethe unit to affect therotation of the supply to change the tension in the material to the saidpredetermined tension.

'5. An apparatus for equalizing the tensions in materials pulled'fromrotatable supplies 'of materials, in combination with a variabledisplacementfluid piston motor-pump unit having a shaft rotatable aboutafixed position axis and a compensator variable with variations -'oftensions to be created in the materials to maintain a selected variablepressure of the fluid in the motor-pumpumt comparable to the tensions tobe created in the materials, the apparatus comprising a U-shaped cradlesupported for rocking' movement between a loading position and theoperating position about the axis of the shaft into and out of anoperating positionand having spindle supporting recesses in the upperends thereof, a spindle, for supporting a supply of pending on thetension to be created in the material pulled off the supply, to normallyurge the cradle with the supply in a direction opposite the direction ofthe pull of the material from the supply, and means operativelyconnecting the spindle and the shaft whereby movement of the inmaterials pulled from rotatable supplies of materials,'in combinationwith a variable displacement fiuidpiston motor-pump unit having a shaftrotatable about a fixed position axis and a compensator, variable withvariations of tensions to be created in the materials to maintain aselected variable pressure of the fluid in the motor-pump unitcomparable to the tensions to be created in the materials, the apparatuscomprising a U-shaped cradle supported for rocking movement. between aleading position and the operating position about the axis of the shaftintoand out of,an operating position and having spindle supportingrecesses in the upper ends thereof, a spindle, for supporting a supplyof material, removably mounted in the recesses of the cradle, a hoodhaving arcuate portions to effectively close the recesses to maintainthe spindle therein, a latch carried by the hood to limit the cradlefrom movement into the loading position, means to connect the supply ofmaterial to the spindle whereby the spindle will be rotated with thesupply when the material is pulled therefrom, means variable, dependingon the tension to be created in the material pulled oil the supply, tonormally urge the cradle with the supply in a direction oppositethedirection of the pull of the material from the supply, and meansoperatively connecting the spindle and the shaft whereby movement of thecradle out of its operating position, as a result of variation of thetension in the material from a predetermined tension, will causevariation in the pressure of the fluid in the unit rendering thecompensator effective to cause the unit to affect the rotation of thesupply to change the tension in the material to the said predeterminedtension.-

- was A. soooa'r.

REFERENCES crrEn The following references areof record in the file ofthis patent:

UNITED STATES PATIENTS Number Name Date 2,206,246 Bannister July 2, 19402,351,264 Harrington June 13, 1944

